Lighting fixture



April 27, 1937. l* H. J. FLAHERTY 2,078,793

` LIGHTING FIXTURE Filed Jan.. 9', 1936 I-iverwtOT: v Harold J.`Hebrew-13% `atented Apr. 27, 1937 PATENT UFFICE LIGHTING FIXTURE HaroldJ. Flaherty, Saugus, Mass., assignor to General Electric Company, acorporation of New York Application January 9, 1936, Serial No. 58,297

1 Claim.

My invention relates -to lighting fixtures and especially to vhighwaylighting xtures wherein the casing of the xture is made of an insulatingmaterial, such as porcelain, and supports the lamp receptacle and theterminals therefor.

One object of my invention is to provide an improved-support forthereceptacle in such units. For a better understanding of my-invention,together-with other and further objects thereof, reference is had to thefollowing description, taken in lconnection with the accompanyingdrawing, and its scope willbe pointed Yout'in the ap- Dended claim. 1

In the aocoin panying drawing, Fig. l illustrates a cross section ofa-lighting unit provided with an improved receptacle support built inaccordance with my invention, and Fig. 2 is an exploded view of thereceptacle and its support.

Referring to the drawing in detail, Fig. 1 illustrates a conventionallighting xture including a cap 5 which is attached to the casing 6 ofthe unit. The casing 6 is a conventional cylindrical hollow casingclosed at its upper end at which the cap is fastened to it in anyconvenient manner, such as by screws l, for example. It is provided witha flange surrounding the outer surface above the line wire terminals 9and I0 and yforming a rain shield therefor. The lower end of the casing6 is open and the edge is perforated to accommodate screws II whichsupport a reflector I2. The screws II are threaded into a ring I3surrounding the outside of the casing 6 and extend through theperforations into the casing to engage the lugs I4 on the reflector I2.A lamp I5, its socket I6 and a receptaclel'l are supported within thecasing 6 by the terminals 9 and I0 and brackets I8 and I5.

The casing 6 is preferably made of an insulating material, such asporcelain, for example, 40 the dimensions of which cannot always be keptwithin the desired limits. It has been found that when manufacturingthese casings in large numbers, various manufacturing errors result incasings varying considerably from the predetermined and desireddimensions. The receptacles to be mounted in the casing's must, however,be mounted so as to maintain a predetermined relationship between thelamp and reflector of each unit. It is also important to obtain thisfinal accuracy at a reasonably low cost. In order to obtain suchaccuracy of receptacle mounting in casings of widely varying dimensions,I have in accordance with my invention provided an improved receptacleand support therefor which may be assembled separately and then mountedwithin the casing, the adjustment of the receptacle and the mountingthereof being done vat substantially the same time.

' Fig. 2 illustrates a receptacle and support built and assembled inaccordance with my invention. The receptacle I'l comprises a disc 20provided with a rectangular opening .2l through which contacts 22 and 23project after `being attached to the underside of the disc 20. The disc2,0 is made of a suitable insulating material, such as porcelain, forexample. The manner of 'assembling the contact 22 with the disc 20 andthe supporting brackets I8 is illustrated by spacingthe elements fromeach other in the order in which they are assembled, thereby creatingwhat 'is commonly termed an exploded view. The contact 23 and bracket I9are illustrated in the assembled relation.

The disc 20 is provided with holes 24 near the edge of the rectangularopening 2| through which screws 25 project and engage the threads inholes 26 of a plate 2l on the upper side of the disc. On the undersideof the disc 20 the screws project through holes 28 of a plate 29,through open-ended slots 3i! in the end of the bracket I8 and throughholes 3| in the end of the contact member 22. When the screws are drawnup into the holes 3l, the contact 22 is attached to the disc andsimultaneously the bracket I8 is held by friction between the plate 29and the contact 22. A direct surface contact is thereby establishedbetween the bracket and receptacle -contact which provides a minimum ofresistance to current flow between the two members. The contact 22 issuitably shaped so that when its lower end is held in contact with thelower surface of disc 2li, the body of the contact projects through therectangular opening and engages at its end the similarly held contact23. The contacts are suiciently resilient to permit the insertionbetween them of the socket contacts 32 and 33 which in` turn areseparated by a dielectric lm cut-out 34.

The brackets I8 and I9 are alike. Each is provided with a vertical arm35 and a horizontal arm 36. The slots 3D are in the end of thishorizontal arm and the vertical arm is provided with spaced holes 3l.Two of these holes are located below the horizontal arm 36 and oneabove. When the brackets and receptacle are assembled, as 5 abovedescribed, the brackets are spaced closely enough to eachother so thatthe assembly may be inserted in the smallest of the casings. When theassembly is then placed inside of a casing, the terminals 9 and I0 areinserted in correspond- 55 ing holes in the brackets selected so as toestablish the proper height of the receptacle within the casings. Theterminals are then turned to draw the vertical arms of the bracketsagainst 5 the wall of the casing. If the casing is of the properdiameter or larger, the brackets are drawn outwardly until they engagethe casing wall. During this process the screws 25 move in the slots3|), the screws having been previously tightened only enough to hold thebrackets in place. If the terminals are simultaneously turned, thebrackets may move outwardly an equal distance leaving the receptaclecentered. If for some reason this receptacle is not properly centered,it may be so centered by simply loosening the screws 25 until thereceptacle may be easily moved. The subsequent tightening of the screwslocks the receptacle in place.

The use of the screws 25 for simultaneously holding the receptaclecontacts and the supporting brackets results in several distinctadvantages. One of these advantages is a reduction of resistance tocurrent flow between the line terminals and the receptacle contacts. Dueto the continual pressure between the contacts and brackets exerted bythe screws, a substantially solid metal conducting path is established.Another advantage is a reduction in manufacturing cost. The eliminationof separate screws and a necessarily separate connecting link betweenthe supporting brackets and the contacts results not only in a saving ofthe cost of these parts but saves considerable time in assembling theparts.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

In a lighting xture, the combination oi a porcelain casing having wallsspaced from each other a distance which may vary from a predetermineddimension, a pair of resilient contacts and means for supporting thesecontacts in a predetermined spaced relation with respect to each othercomprising a pair of metal brackets having vertical arms parallel to theinner walls of said casing and horizontal arms projecting towards thecenter of said casing, means for fastening said vertical arms to saidcasing comprising terminal members projecting through said walls, slotsin the ends of said horizontal arms, a rigid insulating member providedwith spaced holes at predetermined distances from each other, holes inthe ends of said contacts arranged to register with the holes in saidinsulating member, a plate member above said insulating member providedwith threaded holes registering with the holes in said insulatingmember, a second plate under each of said horizontal arms provided withholes registering with said slots and screws arranged to project throughthe said holes in said lower plates, said contacts, said insulatingmember and the slots in said horizontal arms into the threaded holes ofsaid plate member, whereby the contacts'are spaced and held in apredetermined relation with respect to said insulating member and toeach other and are simultaneously clamped to said horizontal armssubstantially centrally Within said insulator casing.

HAROLD J. FLAHERTY.

